Heat sink with multiple micro bosses

ABSTRACT

A heat sink includes multiple heat dissipating fins each with two opposite side walls. Multiple micro bosses are formed on a periphery of the heat dissipating fin. Each heat dissipating fin is securely connected to an adjacent heat dissipating fin via secure engagement between the side walls and a bottom face of the adjacent heat dissipating fin. Each micro boss is in the order between 10 −6  to 10 −9  mm so that laminar effect to decrease heat dissipating capability of the heat sink is avoided.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to a heat sink, and more particularly to a heat sink composed of multiple heat dissipating fins each with multiple micro bosses formed on a periphery of the heat dissipating fin to increase an overall area in contact with air so that heat dissipation effect is increased.

[0003] 2. Description of Related Art

[0004] A conventional approach to increase heat dissipation efficiency is to enlarge the length and/or width of the heat dissipating fins in a heat sink. With the increase of the length and width, the overall exposure area to the air is increased. Therefore, when heat is conducted to the heat dissipating fins, the heat is able to be dissipated by the air flowing by each of the heat dissipating fins. Increasing the heat dissipating efficiency by increasing the length and width of the heat dissipating fins was effective in earlier times, however, due to the available space in high tech electronic devices becoming smaller and smaller, increasing the length and width can no longer solve the problem.

[0005] In order to cope with the existing problem of having smaller and smaller available space and higher and higher heat generated by high speed electronic elements, a novel heat sink is introduced to the market. Each of the heat dissipating fins of the heat sink has multiple bosses formed on a periphery of the heat dissipating fin so that the overall exposure area to the air is increased. Therefore, when air flows through the heat sink, the heat volume on the heat sink and taken away by the air is increased. Using the concept of increasing the overall area of the heat sink exposed to the air so as to increase the heat dissipating volume is practical, inexpensive and reliable. However, a side effect of this type of heat sink is unavoidable. That is, when the air flows around each of the heat dissipating fins, the bosses on each of the heat dissipating fins disturb the air flow, which causes the laminar effect. When there is a laminar effect on a surface, the fluid flowing over the surface is not smooth. Therefore, if the laminar flow occurs on the heat dissipating surface on the heat dissipating fins, the heat dissipating efficiency is seriously influenced and thus degraded. In another word, the heat convection between the heat dissipator and the air is seriously influenced. Thus, heat dissipation effect is decreased.

[0006] To overcome the shortcomings, the present invention tends to provide an improved heat sink to mitigate and obviate the aforementioned problems.

SUMMARY OF THE INVENTION

[0007] The primary objective of the present invention is to provide an improved heat sink with multiple heat dissipating fins each securely connected to one another and having multiple micro bosses on a surface of the heat dissipating fin. Due to the size of the bosses being minimized, the small scale of the laminar flow is not able to influence the air flow over the heat dissipating fins such that the overall heat dissipating volume is increased in that the overall area in contact with the air is increased.

[0008] Another objective of the present invention is to provide an improved heat sink with multiple heat dissipating fins each provided with two side walls oppositely formed on the surface of the heat dissipating fin so that the heat dissipating fin is able to securely connect to an adjacent heat dissipating fin via the opposed side walls.

[0009] Still another object of the present invention is that each heat dissipating fin has a through hole aligning with the through hole of the adjacent heat dissipating fin so that a heat conducting bar is able to extend into the aligned through hole and thus securely engage with each one of the heat dissipating fins.

[0010] Another object of the present invention is that each of the heat dissipating fins has a flange formed around a periphery defining the through hole thus when the heat conducting bar extends into the aligned through holes, the heat conducting bar is able to securely connect to each one of the heat dissipating fins via the flanges.

[0011] Other objects, advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0012]FIG. 1 is a perspective view of the heat sink of the present invention;

[0013]FIG. 2 is a schematic side view showing the inside of the heat sink in FIG. 1;

[0014]FIG. 3 is a schematic view showing the bosses formed on a surface of each of the heat dissipating fins; and

[0015]FIG. 4 is a perspective view showing another preferred embodiment of the heat sink of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0016] With reference to FIGS. 1 and 2, a heat sink in accordance with the present invention has multiple heat dissipating fins (1) and a heat conducting bar (2).

[0017] Each heat dissipating fin (1) has two side walls (11) oppositely formed on two sides of the heat dissipating fin (1), a through hole (12) defined through a periphery of the heat dissipating fin (1) and sandwiched between the two side walls (11) and a flange (13) formed around a periphery defining the through hole (12).

[0018] When the heat sink is in assembly, the multiple heat dissipating fins (1) are securely connected to one another via the side walls (11). After the heat dissipating fins (1) are securely connected to one another, the through holes (12) are aligned with and communicated to each other. The heat conducting bar (2) is extended into the aligned through holes (12) and is securely connected to the flanges (13) of each of the heat dissipating fins (1). After the assembly of the heat sink of the present invention, the heat conducting bar (2) is placed to be in contact with a heat generating element, i.e. a central processing unit (CPU). After operation of the CPU, the generated heat is conducted to the heat conducting bar (2) and then is conducted to the heat dissipating fins (1).

[0019] With reference to FIG. 3, it is noted that each heat dissipating fin (1) has multiple micro bosses (14) formed on a periphery of the heat dissipating fin (1). Each micro boss (14) is in the order of 10⁻⁶ to 10⁻⁹ mm, such that the formation of the micro bosses (14) on the periphery of the heat dissipating fin (1) has only little influence to the air flow over each of the heat dissipating fins (1). That is, because the dimension of the micro bosses (14) is so small that the laminar effect caused by the formation of the micro bosses (14) is negligible. Furthermore, because the overall area of each of the heat dissipating fins (1) to be in contact with the air is increased, the heat dissipating capability is also increased.

[0020] With reference to FIG. 4, another preferred embodiment of the present invention is shown, wherein the heat sink of the present invention in this embodiment has multiple heat dissipating fins (1) each provided with two opposite side walls (11). Each heat dissipating fin (1) is connected to an adjacent heat dissipating fin (1) via engagement between the opposite side walls (11) and a bottom face of the adjacent heat dissipating fin (1). That is, this embodiment is substantially the same as that disclosed in the first embodiment. The only difference therebetween is that the second embodiment does not have the through hole (12) and the heat conducting bar (2).

[0021] In summary, the formation of the micro bosses on the dissipating fins not only increases the heat dissipating capability of the heat sink of the present invention, but also avoids the occurrence of laminar effect which would otherwise decrease the heat dissipating volume.

[0022] It is to be understood, however, that even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed. 

What is claimed is:
 1. A heat sink comprising: multiple heat dissipating fins each provided with two opposite side walls and multiple micro bosses formed on a periphery of the heat dissipating fin; each heat dissipating fin securely connected to an adjacent heat dissipating fin via secure engagement between the side walls and a bottom face of the adjacent heat dissipating fin, wherein each micro boss is in the order between 10⁻⁶ to 10⁻⁹ mm.
 2. The heat sink as claimed in claim 1, wherein each heat dissipating fin further has a through hole and after the heat dissipating fins are securely connected to one another, the through holes are aligned with and communicated to each other.
 3. The heat sink as claimed in claim 2 further comprising a heat conducting bar extending into the aligned through holes to securely engage with each one of the heat dissipating fins.
 4. The heat sink as claimed in claim 2, wherein a flange is formed around a periphery defining the through hole.
 5. The heat sink as claimed in claim 3, wherein a flange is formed around a periphery defining the through hole so that after the heat conducting bar extends into the aligned through holes, the heat conducting bar is able to securely engage with each one of the heat dissipating fins via the flanges. 